The earthmoving industry has been particularly concerned and has expended great effort in attempting to suppress the relatively high noise levels normally generated by large diesel engines employed on earthmoving vehicles. In addition, various governmental regulations now require that the noise levels of such engines not exceed a prescribed maximum.
Numerous attempts have been made to sound-insulate such engines with sound absorbing material to thus lower noise to an acceptable level. However, such attempts have not always proved successful and have substantially increased the complexity and expense of the vehicle. In addition, the airflow patterns over the engine are oftentimes adversely affected, resulting in a loss in engine cooling efficiency.